"Conor Jackson had a big bat and a bright future. But after he contracted a rare illness in 2009 while playing with the Arizona Diamondbacks he was never quite the same."

"Last year another major league baseball player – Ike Davis of the New York Mets – was diagnosed with the same thing.

Valley Fever is on the rise in Arizona. And that could become a problem for Major League Baseball's "Cactus League" – spring training that brings fifteen teams and about 1,000 ballplayers to the Phoenix area from mid-February to late March. A majority of those players are battling for a spot on the major league roster, and an illness that saps your energy is not the way to make that happen."